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Isotopic measurements on junipers growing in southern California during the last glacial, when the ambient atmospheric [CO2] (ca) was ~180 ppm, show the leaf-internal [CO2] (ci) was approaching the modern CO2 compensation point for C3 plants. Despite this, stem growth rates were similar to today. Using a coupled light-use efficiency and tree growth model, we show that it is possible to maintain a stable ci/ca ratio because both vapour pressure deficit and temperature were decreased under glacial conditions at La Brea, and these have compensating effects on the ci/ca ratio. Reduced photorespiration at lower temperatures would partly mitigate the effect of low ci on gross primary production, but maintenance of present-day radial growth also requires a ~27% reduction in the ratio of fine root mass to leaf area. Such a shift was possible due to reduced drought stress under glacial conditions at La Brea. The necessity for changes in allocation in response to changes in [CO2] is consistent with increased below-ground allocation, and the apparent homoeostasis of radial growth, as ca increases today.

Fossil-bearing asphalt deposits are an understudied and potentially significant source of ancient DNA. Previous attempts to extract DNA from skeletons preserved at the Rancho La Brea tar pits in Los Angeles, California, have proven unsuccessful, but it is unclear whether this is due to a lack of endogenous DNA, or if the problem is caused by asphalt-mediated inhibition. In an attempt to test these hypotheses, a recently recovered Columbian mammoth (Mammuthus columbi) skeleton with an unusual pattern of asphalt impregnation was studied. Ultimately, none of the bone samples tested successfully amplified M. columbi DNA. Our work suggests that reagents typically used to remove asphalt from ancient samples also inhibit DNA extraction. Ultimately, we conclude that the probability of recovering ancient DNA from fossils in asphalt deposits is strongly (perhaps fatally) hindered by the organic compounds that permeate the bones and that at the Rancho La Brea tar pits, environmental conditions might not have been ideal for the general preservation of genetic material.

Elizabeth Blackwell's younger sister, Emily (1826–1910), was the third woman to graduate from a regular U.S. medical college in 1854. Unlike the experience of the two women who preceded her, the Chicago medical school that accepted Emily refused to allow her to complete her studies and graduate, forcing her to hastily find an alternative. There was no explanation at the time and the Chicago Tribune, which investigated the incident, could only speculate about the source of such a dishonorable act: "It is very evident there is duplicity and double dealing somewhere. Who is guilty?" Generations of historians have attributed it to Illinois Medical Society pressure against Rush Medical College, but there was no contemporary evidence of such pressure. A closer examination of Blackwell's journal and historical records suggests that Rush founder, president, and professor of surgery, Daniel Brainard engineered her dismissal. One possible motive was a misplaced romantic approach by Brainard. Rush's actions had the paradoxical result of temporarily opening the doors of the Cleveland Medical College (now Case Western Reserve) to four more women medical students. [ABSTRACT FROM AUTHOR]

Introduction: Physician use of online continuing medical education (CME) is growing, but there are conflicting data on the uptake of online CME and few details on this market. Methods: Analyses of 11 years of data from the Accreditation Council for Continuing Medical Education (ACCME) and a survey of 272 publicly available CME Web sites. Results: The data suggest that online CME was 6.9%-8.8% of CME consumed in 2008. If previous exponential growth continues, online CME is likely to be 50% of all CME consumed within 7-10 years. Most (60%) online CME is produced by medical publishing and education companies. The online CME marketplace is consolidating, with 16% of surveyed sites providing 76% of available credits. Currently, 70% of online CME is offered at $10 or less per credit. Most online CME uses low-technology educational approaches, such as pure text and repurposed live lectures. Discussion: Online CME use is growing rapidly and is likely to be half of all CME consumed by practicing physicians within a few years. The pattern is consistent with Christensen's model of "disruptive innovation", whereby an innovative technology eventually displaces an incumbent technology by first providing a relatively low-quality, low-cost product that meets the needs of unserved customers. The technologies being developed for online CME may facilitate broader changes in medical education as well. (Contains 3 tables and 1 figure.)

Introduction: There is a need to provide practicing physicians with training on the recognition and management of intimate partner violence (IPV). Online continuing medical education (CME) could help meet this need, but there is little information on the costs and effectiveness of promoting online CME to physicians. This lack of information may discourage IPV training efforts and the use of online CME in general. Methods: We promoted an interactive, multimedia, online IPV CME program, which offered free CME credit, to 92,000 California physicians for 24 months. We collected data on user satisfaction, the costs of different promotional strategies, and self-reported user referral source. We evaluated California physician awareness of the promotion via telephone surveys. Results: Over 2 years, the CME program was used by 1869 California physicians (2% of market), who rated the program's overall quality highly (4.52 on a 1-5 scale; 5 = excellent). The average promotional cost per physician user was $75. Direct mail was the most effective strategy, costing $143 each for 821 users. E-promotion via search engine advertising and e-mail solicitation had less reach, but was more cost efficient ($30-$80 per user). Strategies with no direct cost, such as notices in professional newsletters, accounted for 31% (578) of physician users. Phone surveys found that 24% of California physicians were aware of the online IPV CME program after 18 months of promotion. Discussion: Promoting online CME, even well-received free CME, to busy community physicians requires resources, in this case at least $75 per physician reached. The effective use of promotional resources needs to be considered when developing social marketing strategies to improve community physician practices. Organizations with an interest in promoting online training might consider the use of e-promotion techniques along with conventional promotion strategies. (Contains 3 tables.)

Introduction: On-line continuing medical education (CME) provides advantages to physicians and to medical educators. Although practicing physicians increasingly use on-line CME to meet their educational needs, the overall use of on-line CME remains limited. There are few data to describe the physicians who use this new educational medium; yet, they clearly are the innovators and early adopters who will facilitate the growth of this educational technology. It would be useful to instructional designers and CME developers to better understand the characteristics of this influential group. Methods: We studied the actual use of several different on-line CME programs within three different groups of physicians. The on-line programs were developed as part of research studies funded by the National Institutes of Health, with no relationship to commercial interests. They were presented to physicians using mass mailouts (two physician groups) or personal contact and were accompanied by incentives to reduce resistance to the new technology. We compared the characteristics of physicians who chose to use these on-line programs with demographic data from larger populations representing the groups from which these users originated. Results: We found that physicians who used these on-line CME programs were younger than average and, importantly, more likely to be female than expected. This finding was consistent across different types of physician populations and different types of CME programs. Discussion: Based on data reflecting actual use of on-line CME, younger physicians appear to be adopting on-line CME more rapidly than others, and women physicians appear to be adopting on-line CME at a faster rate than their male counterparts. This latter finding conflicts with the impression provided by some survey-based studies that male physicians are more likely than female physicians to use on-line CME. The data suggest that the growth of on-line CME is most likely occurring in diffusion networks dominated by relatively new medical school graduates and, possibly, women physicians. These results provide valuable insight to those who seek to develop and market on-line CME and those who seek to reach women physicians with CME programs. (Contains 3 tables.)

Math and the Mouse is an intensive, collaborative, project-driven, study away course that runs during the three-week May Experience term at Furman University and has many of the at- tributes of a course-based undergraduate research experience in mathematics. We take twelve students to Orlando, Florida to study the behind-the-scenes mathematics employed to makeWalt DisneyWorld oper- ate efficiently. Students learn techniques of mathematical modeling (mostly resource allocation, logistics, and scheduling models), statistical analysis (mostly probability, clustering, data collection, and hypoth- esis testing), and ow management (queuing theory and some beginning ow dynamics) in an applied setting. Through planned course modules, collaborative activities, conversations with guest speakers, and three group projects, one of which is of the students' choosing, this academic experience provides an engaged learning experience that shows how material from eleven academic courses comes together in connection with real-world applications. [ABSTRACT FROM AUTHOR]

Lake Turkana itself is a geologically recent phenomenon, but what is now the Lake Turkana basin has an archaeological record that stretches back 2.5 million years and a paleontological record that extends back to the Cretaceous Period. Vertebrate fossils were first discovered in the lower Omo Valley at the beginning of the twentieth century, but the first multidisciplinary international expedition to investigate the region was that of the International Omo Research Expedition in 1967. The National Museums of Kenya participated in the first IORE but thereafter mounted their own multinational and multidisciplinary expeditions to the Kenyan part of the Lake Turkana basin. The Koobi Fora sand spit on the east side of the lake served as the National Museums' field headquarters for the Koobi Fora Research Project on that side of the lake, the subsequent West Turkana Project, more recent fieldwork at Lothagam and Kanapoi, and ongoing field research today. The fossils and artifacts recovered from the Lake Turkana basin have contributed much to our current understanding of early human origins.

The Valley Baseball League is a collegiate summer baseball league with 11 teams playing 42 games between June and August. Producing a schedule has proved challenging for league management, because of the odd number of teams as well as a large number of league mandates and team-specific requests. As an amateur league with limited financial resources, there is pressure to best leverage the league schedule to maximize revenue for each team. A schedule generated by mathematical programming was enthusiastically adopted for the 2020 season and significantly outperformed previous manually produced schedules. [ABSTRACT FROM AUTHOR]